Models of Solar Eruptions: Recent Advances from Theory and Simulations

Abstract

Coronal mass ejections and solar flares are the most stunning manifestations of solar activity. They. are of great scientific and practical interest because solar eruptions and related energetic particle events endanger human life in outer space and pose major hazards for spacecraft in the inner solar system. Coronal mass ejections and flares are presently recognized as two different consequences of a single physical process, which involve a catastrophic loss of mechanical equilibrium of coronal magnetic fields. The actual trigger mechanisms for solar eruptions are, however, not established yet. These mechanisms are the subject of active research and debate by both solar theorists and computational modelers. To improve present knowledge on solar eruptions, any related physical model has to account for two basic properties of the eruption process. These are the fundamental cause of the eruption itself and the nature of morphological features associated with it. This paper summarizes the current understanding of the origin and dynamics of coronal mass ejections through theory and modeling. A strong emphasis is put on the research studies being conducted at the Center for Space Environment Modeling at the University of Michigan. The future prospects for realistic, data-driven modeling of solar eruptions and related solar energetic particle events are also discussed. Once perfected, the models should lead to significant improvements in our ability to forecast those violent solar disturbances that have great impact on the near-Earth environment.